Re: [PATCH v2] powerpc: kernel: fix refcount leak in format_show()

[Michael Ellerman]

On Wed, 2 Mar 2022 10:19:59 +0800, Hangyu Hua wrote:
> Refcount leak will happen when format_show returns failure in multiple
> cases. Unified management of of_node_put can fix this problem.
> 
> 

Applied to powerpc/next.

[1/1] powerpc: kernel: fix refcount leak in format_show()
  https://git.kernel.org/powerpc/c/d601fd24e6964967f115f036a840f4f28488f63f

cheers

Re: [PATCH v2] powerpc: kernel: fix refcount leak in format_show()

[Hangyu Hua]

Any further suggestions for this patch? guys.

Thanks.

On 2022/3/2 10:19, Hangyu Hua wrote:

Refcount leak will happen when format_show returns failure in multiple
cases. Unified management of of_node_put can fix this problem.

Signed-off-by: Hangyu Hua 
---

v2:
1. change the title and description information.
2. fix all possible refcount leak.

  arch/powerpc/kernel/secvar-sysfs.c | 9 ++---
  1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/kernel/secvar-sysfs.c 
b/arch/powerpc/kernel/secvar-sysfs.c
index a0a78aba2083..1ee4640a2641 100644
--- a/arch/powerpc/kernel/secvar-sysfs.c
+++ b/arch/powerpc/kernel/secvar-sysfs.c
@@ -26,15 +26,18 @@ static ssize_t format_show(struct kobject *kobj, struct 
kobj_attribute *attr,
const char *format;
  
  	node = of_find_compatible_node(NULL, NULL, "ibm,secvar-backend");

-   if (!of_device_is_available(node))
-   return -ENODEV;
+   if (!of_device_is_available(node)) {
+   rc = -ENODEV;
+   goto out;
+   }
  
  	rc = of_property_read_string(node, "format", );

if (rc)
-   return rc;
+   goto out;
  
  	rc = sprintf(buf, "%s\n", format);
  
+out:

of_node_put(node);
  
  	return rc;

[PATCH v2] powerpc: kernel: fix refcount leak in format_show()

[Hangyu Hua]

Refcount leak will happen when format_show returns failure in multiple
cases. Unified management of of_node_put can fix this problem.

Signed-off-by: Hangyu Hua 
---

v2: 
1. change the title and description information. 
2. fix all possible refcount leak.

 arch/powerpc/kernel/secvar-sysfs.c | 9 ++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/kernel/secvar-sysfs.c 
b/arch/powerpc/kernel/secvar-sysfs.c
index a0a78aba2083..1ee4640a2641 100644
--- a/arch/powerpc/kernel/secvar-sysfs.c
+++ b/arch/powerpc/kernel/secvar-sysfs.c
@@ -26,15 +26,18 @@ static ssize_t format_show(struct kobject *kobj, struct 
kobj_attribute *attr,
const char *format;
 
node = of_find_compatible_node(NULL, NULL, "ibm,secvar-backend");
-   if (!of_device_is_available(node))
-   return -ENODEV;
+   if (!of_device_is_available(node)) {
+   rc = -ENODEV;
+   goto out;
+   }
 
rc = of_property_read_string(node, "format", );
if (rc)
-   return rc;
+   goto out;
 
rc = sprintf(buf, "%s\n", format);
 
+out:
of_node_put(node);
 
return rc;
-- 
2.25.1